1. Field of the Invention
This invention relates to a viscous material dispenser, and particularly to a multiple use dental syringe having exchangeable tips and/or an integral activator for activating multicomponent capsules.
2. Description of the Related Art
Various dispensing devices for dispensing viscous dental compositions are known in the art, such as, for example, those disclosed in U.S. Pats. Nos. 6,422,866; 6,379,152; 6,135,771; 6,116,414; 6,099,307; 6,059,570; 5,871,355; 5,707,234; 5,489,207; 5,336,088; 5,306,147; 5,267,859; 5,172,807; 5,165,890; 5,125,836; 5,061,179; 4,813,871; 4,619,613; 4,492,576; 4,472,141; 4,384,853; 4,330,280; 4,315,743; 4,295,828; 4,198,756; 4,084,320; 3,828,434; 3,760,503; 3,618,216; 3,581,399; 3,436,828; 3,346,147; 2,903,794; 2,837,824; 2,648,906; 683,075; Des. 461,247; Des. 460,822; Des. 435,292; Des. 359,560; Des. 357,141; Des. 359,119; Des. 357,536; Des. 353,673; Des. 334,803; and Des. 315,956; the subject matter of all of which are hereby incorporated by reference in their entireties.
U.S. Pat. No. 4,472,141 to Dragan discloses an attempt to achieve an all purpose dental syringe and delivery system for dispensing various types of dental materials. The Dragan syringe includes a power handle having a plunger that is incrementally advanced upon each actuation of the power handle and a plurality of interchangeable barrel assemblies, each with an associated dispensing nozzle. Dragan also discloses interchangeable plunger tips co-operatively associated with the plunger for complementing a particular barrel assembly.
However, providing interchangeable barrel assemblies including tips increases the costs incurred in a syringe device. Additionally, requiring the end user to remove a barrel, remove an associated plunger tip, replace the plunger tip with a different plunger tip, and then install a different barrel can be a time consuming procedure for the end user of the syringe device.
Additionally, certain viscous dental composition cartridges contain two or more separated components that must be mixed before application of the composition to a patient. Generally, a device that is separate from the dental syringe is used to break a frangible seal or the like separating the components. For example, in one conventional device, the cartridge is inserted into a slot and a device is used to apply pressure against the walls of the cartridge, breaking the seal separating the components and thus activating the viscous composition.